[PATCH v3 03/31] str: Fix a few bugs in trailing_strtoln()

[Simon Glass]

Hi Rasmus,

On Mon, 31 Jan 2022 at 02:44, Rasmus Villemoes
<rasmus.villemoes at prevas.dk> wrote:
>
> On 19/01/2022 02.42, Simon Glass wrote:
> > At present this has a minor bug in that it reads the byte before the
> > start of the string.
>
> Only for an empty string, AFAICS. Which is a bug, of course, but mostly
> the caller is to blame.

Yes

>
> Also it doesn't handle a non-numeric prefix which is
> > only one character long.
> >
> > Fix these bugs with a reworked implementation.
>
> How does your new implementation handle the case of no prefix at all,
> i.e. "456"? Shouldn't that also work? Or a single-digit "7"?

It is not designed to work for that case. You could just use dectoul()
or similar.

>
> Both the old and new seem to have a bug in that the end parameter is
> essentially ignored. If I have
>
> const char *s = "abc123";
>
> and do
>
> trailing_strtoln(s, s+5);
>
> I'd expect 12.

That is intentional though - end is expected to point to a letter. I
can reword the function comment to cover both of these cases.

Regards,
Simon